n00b asked... Do you have the lowside in the 3/16? (as in the evap?)
No I used 1/4"od for the evaporator and return line, didn't want too much of a pressure drop since the evap used a fairly good length of it. I suppose if we were talking about making an evap suitable for PC Cooling it could be made out of 3/16"od without a problem.

n00b also asked... Your gas selection is very nice though, you must have access to many many nice refrigerants.
Yeah it's nice that I often times do contract work for a Polycold related service company (M&T Systems). They have R-22, R-123, R-23, R-14, Ethane, and Argon in ready supply.
Lets me be a real mad scientist